Crown block lifting steel wire rope groove-disengaging-preventing power-off safety protection device
By designing a safety protection device for anti-drooting and power-off of the Tianche lifting wire rope including heavy hammer limit switch, steel wire rope, heavy hammer, bumper rod, limit switch and connecting rod, the problem of detachment of the Tianche lifting wire rope is solved, and the safe operation of the equipment and accident prevention are achieved.
Patent Information
- Application Number
- CN202421623128.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-10
- Publication Date
- 2025-05-30
- Estimated Expiration
- 2034-07-10
AI Technical Summary
The lifting wire rope of the sky car is prone to detachment during use, resulting in major safety accidents in the equipment.
A safety protection device for anti-drooting and power-off of the steel wire rope at the sky car is designed, including a heavy hammer limit switch, a steel wire rope, a heavy hammer, a bumper rod, a limit switch and a connecting rod. Through the swing of the heavy hammer and the bumper rod, the connecting rod touches the limit switch, disconnecting the control system's circuit and preventing the wire rope from being disconnected.
It effectively prevents the occurrence of wire rope detachment accidents from lifting the sky car, improves the operating rate and safety of the equipment, and reduces the failure rate and maintenance costs.
Smart Images
Figure CN222922796U_ABST
Abstract
Description
Technical Field
[0001] This patent application belongs to the technical field of safety protection devices for overhead crane hoisting wire ropes. More specifically, it relates to a power-off safety protection device for preventing the overhead crane hoisting wire rope from slipping out of the groove. Background Art
[0002] The hoisting mechanism of an overhead crane is the core mechanism in the transmission mechanism of the overhead crane. During the use of the overhead crane, the operator's pulling at an angle or operating errors may cause the overhead crane wire rope to slip out of the fixed small pulley, and then a wire rope out-of-groove accident may occur. Since the fixed small pulley is located on the overhead crane trolley and at a high altitude in the workshop, the discovery period is relatively long, which is likely to cause wire rope broken wires and wear of the main shaft of the fixed small pulley. At the same time, the wire rope after slipping out of the groove is wound irregularly, resulting in wire rope jamming and breaking, small pulley jamming and wear. Severe wear of the wheel shaft will cause the fixed small pulley to fall from the overhead crane body. In the long run, it is easy to cause serious wear and fracture of the core shaft of the small pulley or major equipment accidents and safety accidents such as wire rope strand breaks and root breaks. The wire rope after slipping out of the groove will also affect the wire rope life and endanger production safety. Whether the hoisting mechanism of the overhead crane can operate smoothly and safely determines the hoisting efficiency and quality of the overhead crane, and also determines the necessary conditions for the smooth progress of production.
[0003] R & D personnel analyzed the causes of major equipment accidents of domestic overhead cranes. Once an equipment accident occurs in the hoisting mechanism of an overhead crane, it will cause major safety accidents of the equipment. In the actual use of overhead cranes, cases of major safety accidents caused by wire rope out-of-groove due to pulling at an angle are common. By analyzing the causes of major equipment accidents of overhead cranes, it is found that the fundamental problem of safety accidents caused by the out-of-groove of the overhead crane hoisting wire rope needs to be further solved.
[0004] Therefore, in the context of frequent problems with the hook wire rope of the overhead crane hoisting mechanism slipping out of the fixed small pulley on the trolley, it is urgent to research and develop and use a device that can protect the overhead crane hoisting wire rope from slipping out of the groove. Utility Model Content
[0005] The technical problem to be solved by this utility model is to provide a power-off safety protection device for preventing the overhead crane hoisting wire rope from slipping out of the groove to solve the technical problem of frequent slipping out of the hoisting wire rope in the existing technical design.
[0006] To solve the above problems, the technical solution adopted by this utility model is:
[0007] An anti-derailment power-off safety protection device for the hoisting wire rope of a overhead crane, comprising a weight limit switch fixed on the bottom plate of the trolley, a wire rope correspondingly connected to the weight limit switch, a weight arranged at the bottom end of the wire rope, a bumper rod fixedly connected to the weight and arranged at the bottom of the bottom plate of the trolley, two limit switches arranged on the bottom plate of the trolley and on one side of the weight limit switch, and a connecting rod located between the contacts of the two limit switches and fixed to the lower part of the bottom plate of the trolley. An opening is made at the lower end of the connecting rod and then connected to the bumper rod of the weight. A bolt is fixed at the bottom end of the connecting rod;
[0008] The weight is fixed on the bumper rod by screws;
[0009] The normally closed contact of the weight switch of the weight limit switch and the normally closed contacts of the two limit switches are connected in series in the control system of the overhead crane hoisting mechanism.
[0010] Furthermore, it further comprises a small pulley. The outer wheel of the small pulley is fixed on the lower cross beam of the bottom plate of the trolley, and the inner sleeve of the bearing of the small pulley is fixedly connected to the connecting rod. The function of the small pulley is to support the weight of the connecting rod and swing left and right as the bumper rod swings left and right, while the connecting rod on the upper part of the bottom plate of the trolley swings left and right in the opposite direction. When the swing amplitude is large, it will trigger the two limit switches to act.
[0011] Furthermore, the outer wheel of the small pulley is welded to the lower cross beam of the bottom plate of the trolley through an angle steel bracket, the inner sleeve of the bearing of the small pulley is fixedly connected to the connecting rod by screws, and a gasket is used to isolate and prevent friction between the outer wheel of the small pulley and the connecting rod.
[0012] Furthermore, the limit switches are selected as whisker type limit switches. The limit switches are connected to the bottom plate of the trolley through limit switch bases. The two limit switches are arranged left and right, and the protruding connecting rod is located between the two limit switches.
[0013] Furthermore, the weight limit switch is equipped with a weight limit counterweight. The weight limit counterweight is connected to the weight through a wire rope. The bumper rod is L-shaped and includes a vertical rod and a horizontal rod connected vertically. The vertical rod is fixed on the cross beam at the bottom of the bottom plate of the trolley. An opening is provided at the lower end of the connecting rod 4, and the horizontal rod passes through the opening. The horizontal rod is connected to the lower end of the connecting rod. The thickness of the opening is greater than the thickness of the horizontal rod, and the height is greater than the height required for the weight limit counterweight 13 to descend. The opening at the lower end of the connecting rod is greater than the height of the horizontal rod.
[0014] Furthermore, a reserved opening is provided on the bottom plate of the trolley, and the connecting rod passes through the reserved opening on the bottom plate of the trolley.
[0015] Furthermore, the reserved opening on the bottom plate of the trolley is rectangular.
[0016] Due to the adoption of the above technical solutions, the beneficial effects obtained by the present utility model are:
[0017] The anti-derailment power-off safety protection device for the overhead crane hoisting wire rope provided by the present invention can cause the wire rope to swing violently and sway greatly left and right due to the overhead crane hook being pulled obliquely or illegally operated. The weight hitting rod sways together under the drive of the wire rope. The lower end of the connecting rod swings together with the hitting rod under the drive of the weight hitting rod. The upper end of the connecting rod moves in the opposite direction under the action of the small pulley fulcrum, touches the left and right limit switch contact rods and moves, cuts off the zero-position line connected in series in the hoisting mechanism control system, and the wire rope of the hoisting mechanism cannot move, avoiding the occurrence of the accident that the wire rope derails from the fixed small pulley due to the hoisting or lowering of the wire rope by oblique pulling.
[0018] Furthermore, for the anti-derailment power-off safety protection device for the overhead crane hoisting wire rope provided by the present invention, only the hoisting mechanism is controlled to cut off the power, and the large and small cars of the overhead crane can operate and be used normally. As long as the hook and the wire rope are in a vertically perpendicular state, after the connecting rod is vertical, the limit switch can reset itself under the action of its own spring, and the hoisting mechanism can automatically return to the normal state for use.
[0019] Furthermore, after the anti-derailment power-off safety protection device for the overhead crane hoisting wire rope is assembled, the height of the connecting rod protruding from the bottom plate of the small car exceeds the height of the limit switch by 15 cm. The distance between the connecting rod and the limit switch contact rod can be adjusted according to the actual situation on site. In this way, no matter in what working conditions there is illegal operation or oblique pulling and slanting lifting, the hoisting mechanism can cut off the power in the first time, and the hoisting mechanism cannot work, effectively preventing the occurrence of the wire rope derailment accident, improving the equipment operation rate, reducing the equipment failure rate and maintenance cost, and at the same time preventing the occurrence of major safety accidents such as the shaft breakage of the hoisting mechanism and the fracture of the wire rope. The device has a simple structure, good safety, low failure rate, and low use and maintenance costs. BRIEF DESCRIPTION OF THE DRAWINGS
[0020] Figure 1 It is a schematic structural diagram of the device.
[0021] Figure 2 It is a schematic side view structure diagram of the limit switch in the device.
[0022] Figure 3 It is a schematic connection diagram of the limit switch in the hoisting control system of the device.
[0023] Figure 4 It is a schematic fixation diagram of the connecting rod in the device.
[0024] Figure 5 It is a schematic connection diagram of the weight limit counterweight in the device.
[0025] Wherein: 1. Hammer limit switch, 2. Small pulley, 3. Limit switch, 4. Connecting rod, 5. Bolt, 6. Hammer, 7. Steel wire rope, 8. Bumper rod, 9. Trolley bottom plate, 201. Reserved opening on the trolley bottom plate, 301. Normally closed contact of the hammer switch, 302. First normally closed contact of the limit switch, 303. Second normally closed contact of the limit switch, 11. Pulley, 12. Lifting rope, 13. Counterweight for the hammer limit switch. Specific embodiments
[0026] The present utility model will be further described in detail below in conjunction with embodiments.
[0027] A safety protection device for preventing the steel wire rope of a crane from slipping out of the groove and cutting off the power supply. This device is mainly invented based on the idea that when the crane hook is lifted and lowered, as long as the hook and the steel wire rope are in a vertically lead state, they will not slip out of the small fixed pulley groove. If the crane hook is pulled obliquely or swings for other reasons, it will drive the mechanical bumper rod and the connecting rod to deflect in position and touch the limit switch on the trolley, thereby cutting off the power supply of the lifting mechanism control system and avoiding the accident of the steel wire rope 7 slipping out of the groove.
[0028] The specific structure is as Figure 1 , and it includes a hammer limit switch 1, a small pulley 2, a limit switch 3, a connecting rod 4, a bolt 5, a connecting plate, a hammer 6, a steel wire rope 7, and a bumper rod 8. The hammer limit switch 1 is fixed on the trolley bottom plate 9. The top of the steel wire rope 7 corresponds to the hammer limit switch 1, and the bottom end is connected to the hammer 6. The bumper rod 8 is fixedly connected to the hammer 6 and is arranged at the bottom of the trolley bottom plate 9.
[0029] Figure 1 , Figure 5 In, the hammer limit switch 1 is equipped with a counterweight 13 for the hammer limit switch. The counterweight 13 for the hammer limit switch is connected to the hammer 6 through the steel wire rope 7. The bumper rod 8 is L-shaped and includes a vertical rod and a horizontal rod connected perpendicularly. The vertical rod is fixed on the crossbeam at the bottom of the trolley bottom plate 9. The lower end of the connecting rod 4 is provided with an opening, and the horizontal rod passes through the opening. The horizontal rod is connected to the lower end of the connecting rod 4. The thickness of the above-mentioned opening is greater than the thickness of the horizontal rod, and the height is greater than the height required for the counterweight 13 for the hammer limit switch to drop. This is beneficial for the hammer 6 and the horizontal rod to have enough rising space for the counterweight 13 for the hammer limit switch to hang freely and play its role.
[0030] The opening provided at the lower end of the connecting rod 4, and the horizontal rod of the bumper rod 8 passes through the opening. When designing, the thickness of the opening is slightly greater than the thickness of the horizontal rod, and the height should be slightly greater than the height required for the counterweight 13 for the hammer limit switch to drop. The bottom opening of the opening is the "lower end opening", and the bottom end of the "lower end opening" is fixed with a bolt 5 to prevent it from falling off by itself. This is beneficial for the hammer 6 and the horizontal rod to have enough rising space for the counterweight 13 for the hammer limit switch to hang freely and play its role. The counterweight 13 for the hammer limit switch is one of the structural components of the hammer limit switch 1, as Figure 5 shown.
[0031] Two limit switches 3 are arranged on the trolley bottom plate 9, and their circuits are connected in series. Specifically, the normally closed contact 301 of the weight switch of the weight limit switch 1 and the normally closed contacts of the two limit switches 3 are connected in series in the overhead crane hoisting mechanism control system.
[0032] Between the contacts of the two limit switches 3 is a connecting rod 4, and the connecting rod 4 is fixed to the lower part of the trolley bottom plate 9. As Figure 2 shown, the connecting rod 4 passes through the reserved opening 201 of the trolley bottom plate. The connecting rod 4 is fixed to the angle steel below the trolley bottom plate 9 through the small pulley 2 and the bracket. After the end of the lower part of the connecting rod 4 is drilled, it is sleeved on the bumper rod 8 of the weight 6. The end of the lower part of the connecting rod 4 is then fixed with bolts. By sleeving the connecting rod 4 on the bumper rod 8 and then fixing it with bolts, it is perpendicular to the surface of the bumper rod 8 vertically. It is fixed to the trolley bottom plate 9 through the small pulley 2 and the bracket, realizing the function that the connecting rod 4 swings left and right following the bumper rod 8.
[0033] The outer wheel of the small pulley 2 is fixed on the lower cross beam of the trolley bottom plate 9, and the inner sleeve of the bearing of the small pulley 2 is fixedly connected to the upper part of the connecting rod 4. The function of the small pulley 2 is to support the weight of the connecting rod 4 and swing left and right as the bumper rod 8 swings left and right, while the part of the connecting rod 4 above the trolley bottom plate 9 swings left and right in the opposite direction. When the swing amplitude is large, it touches the two limit switches 3 to actuate.
[0034] The specific installation is as follows: The outer wheel of the small pulley 2 is welded to the lower cross beam of the trolley bottom plate 9 through an angle steel bracket, and the inner sleeve of the bearing of the small pulley 2 is fixedly connected to the upper part of the connecting rod 4 through screws. A gasket is used to isolate and prevent friction between the outer wheel of the small pulley 2 and the connecting rod 4.
[0035] During use, as Figure 1 、 Figure 2 shown, the connecting rod 4 passing through the reserved opening 201 of the trolley bottom plate is fixed to the small pulley 2 by welding, and the core shaft of the small pulley 2 is welded to the trolley bottom plate 9. This design can effectively realize the function that the connecting rod 4 swings left and right following the weight 6 and the bumper rod 8. A margin should be left when the end of the lower part of the connecting rod 4 and the bumper rod 8 are sleeved together and fixed to prevent the failure of the weight limit counterweight 13 caused by the inability of the connecting rod 4 to move up and down.
[0036] As Figure 2As shown in the figure, the range where the connecting rod 4 passes through the reserved opening 201 on the trolley bottom plate directly affects the sensitivity of the free swing of the connecting rod 4 and the contact with the contact rod of the limit switch 3; the reserved opening 201 on the trolley bottom plate is long enough and its shape is rectangular, which is convenient for leaving enough left and right swing strokes for the connecting rod 4. Otherwise, the connecting rod 4 may be damaged due to a large swing amplitude; it is more appropriate to select a whisker-type limit switch 3; the distances between the connecting rod 4 and the contact rods of the two limit switches 3 need to be adjusted appropriately according to the actual situation on site. Only through continuous testing, after the connecting rod 4 and the contact rod of the limit switch 3 are in the appropriate position and at the appropriate distance, can the connecting rod 4 play its role with the maximum sensitivity. In this way, before the overhead crane wire rope 7 tilts at a certain angle and does not come out of the fixed pulley of the hook wire rope 7, a safety protection measure for power-off of the overhead crane hoisting mechanism control system can be realized.
[0037] The range where the connecting rod 4 passes through the reserved hole 201 on the trolley bottom plate directly affects the sensitivity of the free swing of the connecting rod 4 and the contact with the contact rod of the limit switch 3. The distances between the connecting rod 4 and the contact rods of the two limit switches 3 should be appropriate. By continuous testing and installing the two limit switches 3 at the appropriate position and distance, a safety protection measure for power-off of the hoisting mechanism can be realized before the wire rope 7 tilts at a certain angle and does not come out of the wire rope 7.
[0038] The limit switch 3 is selected as a whisker-type limit switch. The limit switch 3 is connected to the trolley bottom plate 9 through a limit switch base. The two limit switches 3 are arranged left and right, and the protruding connecting rod 4 is located between the two limit switches 3.
[0039] As Figure 3 shown, the normally closed contact 301 of the weight switch is in the circuit Figure 3 Among them, the normally closed contacts of the two limit switches are the normally closed contact one 302 of the limit switch and the normally closed contact two 303 of the limit switch respectively. The normally closed contact one 302 of the limit switch and the normally closed contact two 303 of the limit switch are connected in series in the zero-position relay circuit of the hoisting mechanism control system. That is, the normally closed contact one 302 of the limit switch is the normally closed contact of one of the limit switches, and the normally closed contact two 303 of the limit switch is the normally closed contact of the other limit switch. After the two normally closed contacts of the limit switches are connected in series, they are then connected in series in the zero-position relay circuit of the hoisting mechanism control system. As long as the wire rope 7 is pulled obliquely and the connecting rod 4 touches the contact rod of any one of the limit switches 3 and the contact point is disconnected, the zero-position relay of the hoisting mechanism control system loses power and disconnects, and the hoisting main circuit controlled by the hoisting control system cannot work, realizing that the hook wire rope 7 driven by the hoisting mechanism motor neither rises nor falls. After the wire rope 7 does not move, it cannot come out of the hook fixed pulley groove, realizing the power-off safety protection function.
[0040] The present invention provides an anti-derailment power-off safety protection device for the hoisting wire rope of a crane. During the hoisting process of the crane, the pulley 11 operates through the hoisting rope 12. When illegal operation or oblique pulling and slanting lifting occur, a certain angle displacement will be caused between the hook wire rope 7 and the vertical trolley hook fixed pulley, resulting in the wire rope 7 slipping out of the hook fixed pulley groove. The limit switch of this device can make the wire rope 7 of the crane touch the contact rod of the limit switch 3 when it swings left and right to reach the position of ±15°, and the zero-position relay of the main hoisting control system is powered off and fails. After debugging this device, under any working conditions, whether it is oblique pulling and slanting lifting or the lifted object hitting the bottom, the hoisting mechanism can be powered off immediately, without affecting the operation of the trolley mechanism and the crab mechanism of the crane. As long as the wire rope 7 returns to the vertical position, the zero-position relay of the hoisting mechanism is automatically restored. It effectively prevents the occurrence of accidents of the wire rope 7 slipping out of the groove due to oblique pulling and slanting lifting, improves the equipment operation rate, reduces the equipment failure rate and maintenance cost, and at the same time prevents the occurrence of major safety accidents such as the shaft breakage of the hook fixed pulley of the hoisting mechanism and the breakage of the wire rope.
Claims
1. A safety device for preventing the lifting wire rope of an overhead crane from falling out of the groove and for preventing the wire rope from falling out of the groove, characterized in that: The invention comprises a weight limit switch (1) fixed on a trolley bottom plate (9), a steel wire rope (7) correspondingly connected to the weight limit switch (1), a weight (6) arranged at the bottom end of the steel wire rope (7), a contact rod (8) fixedly connected to the weight (6) and arranged at the bottom of the trolley bottom plate (9), two limit switches (3) arranged on the trolley bottom plate (9) and located on one side of the weight limit switch (1), and a connecting rod (4) located between the contacts of the two limit switches (3) and fixed to the lower part of the trolley bottom plate (9), the lower end of the connecting rod (4) being connected to the contact rod (8) of the weight (6) after a hole is opened, and a bolt (5) is fixed to the lower end of the connecting rod (4); The weight (6) is fixed to the impact rod (8) by screws; The normally closed contact (301) of the heavy hammer limit switch (1) and the normally closed contacts of the two limit switches (3) are connected in series in the control system of the overhead crane hoisting mechanism.
2. The power-off safety protection device for preventing the lifting wire rope of an overhead crane from falling out of the groove according to claim 1 is characterized in that: It also includes a small pulley (2), the outer wheel of the small pulley (2) is fixed on the lower cross beam of the trolley bottom plate (9), and the inner sleeve of the bearing of the small pulley (2) is fixedly connected to the connecting rod (4).
3. The power-off safety protection device for preventing the lifting wire rope of an overhead crane from falling out of the groove according to claim 2 is characterized in that: The outer wheel of the small pulley (2) is welded to the lower cross beam of the trolley bottom plate (9) through an angle steel bracket, the inner sleeve of the bearing of the small pulley (2) is fixedly connected to the connecting rod (4) through screws, and the outer wheel of the small pulley (2) and the connecting rod (4) are isolated by a gasket.
4. The power-off safety protection device for preventing the lifting wire rope of an overhead crane from falling out of the groove according to claim 1 is characterized in that: The limit switch (3) is a tentacle-type limit switch, and the limit switch (3) is connected to the bottom plate (9) of the trolley through a limit switch base. The two limit switches (3) are arranged on the left and right, and the extended connecting rod (4) is located between the two limit switches (3).
5. The power-off safety protection device for preventing the lifting wire rope of an overhead crane from falling out of the groove according to claim 1 is characterized in that: The weight limit switch (1) is equipped with a weight limit counterweight (13), the weight limit counterweight (13) is connected to the weight (6) through a wire rope (7), the contact rod (8) is L-shaped, and includes a vertical rod and a horizontal rod connected vertically, the vertical rod is fixed on the crossbeam at the bottom of the trolley bottom plate (9), the lower end of the connecting rod (4) is provided with an opening, the horizontal rod passes through the opening, the thickness of the opening is greater than the thickness of the horizontal rod, and the height is greater than the height required for the weight limit counterweight (13) to descend.
6. A power-off safety protection device for preventing the lifting wire rope of an overhead crane from falling out of a groove according to any one of claims 1 to 5, characterized in that: The trolley bottom plate (9) is provided with a trolley bottom plate reserved opening (201), and the connecting rod (4) passes through the trolley bottom plate reserved opening (201).
7. The power-off safety protection device for preventing the lifting wire rope of an overhead crane from falling out of the groove according to claim 6 is characterized in that: The reserved opening (201) of the bottom plate of the trolley is rectangular.